Comparison of effects of chenodeoxycholic and ursodeoxycholic acid and their combination on biliary lipids in obese patients with gallstones.

To study the effects of different bile acids on biliary lipids in obese patients with radiolucent gallstones, 12 subjects were given chenodeoxycholic acid (CDCA) at a dose of 15 mg/kg/day, ursodeoxycholic acid (UDCA) at a dose of 15 mg/kg/day, and an equimolar combination of the two (7.5 + 7.5 mg/kg/day) in accordance with a double-blind crossover design. Mean molar percentage of cholesterol and cholesterol saturation index corrected for urso-rich bile (CSI) decreased significantly with all three treatments, but the combination was more effective in decreasing the CSI than either of the two bile acids given alone (p less than 0.05). Bile became desaturated in 10 of 12 patients receiving the combination, in 4 of 12 receiving CDCA, and 3 of 12 receiving UDCA alone. Combination treatment was well tolerated since mild diarrhea and slight increase in transaminases were observed only in a few patients. We conclude that the combined administration of CDCA and UDCA in equimolar doses is the treatment of choice for dissolution of gallstones in obese patients.